KR100236202B1 - Substrate baking apparatus and substrate baking method - Google Patents

Abstract

An object of the present invention is to provide a substrate baking apparatus and a substrate baking method capable of improving the uniformity of the in-plane temperature of a substrate during a baking step.

To this end, the present invention comprises a lower heating plate 21 on which a photoresist substrate 16 is placed, an upper heating plate 26 disposed above the heating plate 21, A crack ring 23 provided on the heating plate 21, and a chamber 27 for sealingly storing the whole.

Description

Substrate baking apparatus and method for baking substrate (AN APPARATUS FOR BAKING A SUBSTRATE FOR PHOTO MASK AND A METHOD THEREOF)

FIG. 1 is a plan view showing the entire structure in the case where the baking apparatus according to the present invention is carried out for baking a photomask substrate,

FIG. 2 is a cross-sectional view showing a detailed configuration of the baking chamber portion in the baking apparatus of FIG. 1,

3 is a cross-sectional view of the lower heating plate in the baking chamber portion of FIG. 2,

4 is a plan view of the crack ring in the baking chamber portion of FIG. 2,

5 is a plan view of the upper heating plate in the baking chamber of FIG. 2,

6 shows a general photolithographic process,

FIG. 7 is a characteristic diagram showing the result of comparing the in-plane average temperature and the in-plane temperature error state of the substrate at the time of the temperature increase in the pre-baking step of FIG.

FIG. 8 is a front view showing a detailed configuration of the cooling section in the baking apparatus of FIG. 1;

FIG. 9 is a sectional view showing the configuration of a modified example of the upper heating plate,

FIG. 10 is a cross-sectional view showing a configuration of a modified example of the baking chamber portion in the baking apparatus of FIG. 1,

11 is a cross-sectional view of a modification of the lower heating plate,

12 is a sectional view showing the configuration of another modification of the baking chamber portion in the baking apparatus of FIG. 1;

13 is a cross-sectional view of a conventional baking apparatus.

DESCRIPTION OF THE REFERENCE NUMERALS

11: baking chamber part 12: cooling part

13: transport mechanism part 14: substrate carrier

15: Operation panel 16: Photomask substrate

21: lower heating plate 22: groove (groove)

23: crack ring 24: tapered portion

25: storage part 26: upper heating plate

27: chamber (container) 28: gas injection hole

29: gas supply means 30: open

31: opening 32: exhausting means

41: heating plate 42: heater

43: thermocouple 44: thermostat

51: cooling plate 52a to 52d: pin

53: Nozzle 54:

55: rectification plate 56: screw

57: air cylinder 58: injection hole

61: Cavity 62: Home

63: arm 64: ball screw

65: Motor

[Industrial Applications]

The present invention relates to a substrate baking apparatus and a substrate baking method for performing baking of a semiconductor substrate and a liquid crystal substrate by using photolithography.

[Background Art and Problems]

A photomask used in a photolithography technique for manufacturing a semiconductor device is formed by sputtering Cr (chrome) on a quartz substrate, applying a photoresist thereon, pre-baking and drawing a pattern using an electron beam drawing apparatus, Resist development processing, post bake, selective etching of a metal thin film, resist stripping, and the like.

In the conventional lithography technique, the resolution of the pattern dimensions and the uniformity of the dimensions within the substrate surface are not so strictly required, and the photoresist to be used does not depend on the temperature variation of the baking apparatus.

Here, a conventional baking apparatus used in the photomask baking step will be described with reference to a cross-sectional view of FIG. As shown in the drawing, a conventional baking apparatus is merely provided with a heating plate 71, and a substrate 72 made of quartz or the like coated with a photoresist is formed on the heating plate 71 at intervals of several tens of microns So that a predetermined time of baking is performed. Reference numeral 73 in the drawings denotes a seal member for securing the proximity gap. That is, conventionally, the substrate 72 is baked under an open system (open system), and after baking is separated from the heating plate 71, it is naturally cooled at room temperature.

However, in recent photolithography techniques, the resolution of the pattern dimensions and the uniformity of the dimensions in the surface of the substrate become strict with the miniaturization of semiconductor devices. Under such circumstances, a chemically amplified resist having high resolution has started to be put into practical use. As a representative example thereof, there is SAL601 of Syphre. It is known that the chemical amplification type resist is subjected to a crosslinking reaction (negative type) and a decomposition reaction (positive type). From this point of view, it is generally known that the pattern dimension is significantly influenced by heat treatment such as baking. Therefore, there is a need for a high-performance baking apparatus having high uniformity of dimensions within the substrate surface.

However, in the conventional baking apparatus, since the influence of the ambient air current and the surrounding heat source is directly affected, the in-plane temperature fluctuation of the heating plate becomes large, and a large temperature difference is seen at the central portion and the peripheral portion of the substrate during the baking process. For example, when using a 6-inch mask (a quartz substrate of 152.4 × 152.4 × 6.4 mm) and setting the baking temperature to 120 ° C., the temperature difference within the substrate surface at the transition temperature (63 ° C.) 109 ° C), the temperature difference within the substrate surface is 7.2 ° C, and a very large in-plane temperature difference is generated in both transient and temperature stabilizers. Since the chemically amplified resist is baked at about 100 DEG C to conduct sensitivity amplification, the pattern dimension largely changes due to the uniformity of the temperature during baking. Therefore, it has been found that the pattern-formed substrate after the resist developing process, the selective etching of the metal thin film, and the resist peeling process become very fatal because the in-plane dimensional error becomes very large and does not fall within the standard.

In some cases, the substrate is directly placed on the heating plate without mediating the proximity gap as described above. In this case, the temperature error in the substrate surface becomes larger.

Furthermore, in the conventional baking apparatus, since the heating plate is opened to the outside air, the dust tends to adhere to the resist during the baking process, which also causes defects.

As described above, in the conventional baking apparatus, a large in-plane temperature difference is generated in the substrate during the baking process, and there is a drawback that the in-plane dimensional error greatly increases after completion.

[Object of the invention]

It is an object of the present invention to provide a substrate baking apparatus and a substrate baking method capable of improving the uniformity of the in-plane temperature of the substrate during the baking process.

SUMMARY OF THE INVENTION [

The substrate baking apparatus of the first invention is a substrate baking apparatus comprising a first heating plate on which a photoresist is applied and on which a baking substrate is placed directly or at a predetermined interval and a second heating plate, A heating plate; a cracking plate provided on the first heating plate so as to surround the periphery of the baking substrate; and a container for housing the first and second heating plates and the cracking plate.

A substrate baking apparatus according to a second aspect of the present invention is a substrate baking apparatus comprising a first heating plate on which a photoresist is applied and on which a baking substrate is placed directly or with a predetermined gap therebetween, A second heating plate provided so as to be close to a peripheral portion of the substrate to be baked, a crack plate provided on the first heating plate so as to surround the periphery of the substrate, a first heating plate and a second heating plate, And a cooling plate for cooling the substrate and the substrate to be baked.

A third aspect of the present invention is a method for baking a substrate on which a photoresist is applied, the method comprising the steps of: positioning a baked substrate on a cooling plate for a predetermined time to uniformize the temperature of the baked substrate; The substrate is placed on a first heating plate and the periphery of the substrate to be baked is surrounded by a crack plate and the second heating plate is placed above the photoresist application surface of the substrate to be baked.

A fourth aspect of the present invention is a method for baking a substrate on which a photoresist is applied, the method comprising the steps of: cooling a baked substrate to uniformize the temperature of the baked substrate; The periphery of the substrate to be baked is surrounded by a cracking plate and the second heating plate is placed above the coated surface of the photoresist on the substrate to be baked. Then, the baked substrate after the heating is placed on the cooling plate, And the substrate is cooled by discharging cooling gas onto the substrate.

[Action]

In the substrate baking apparatus according to the first aspect of the present invention, the temperature difference between the in-plane of the substrate to be baked can be made uniform by surrounding the substrate with the first and second heating plates and the cracking plate and heating the entire substrate.

In the substrate baking apparatus according to the second aspect of the present invention, the temperature difference between the inner surface of the substrate to be baked can be made uniform by performing heating in a state in which the lower surface of the second heating plate is close to the peripheral portion of the substrate.

In the substrate baking method of the third invention, the baking substrate is cooled for a predetermined time to equalize the temperature, and then the baking substrate is surrounded by the first and second heating plates and the cracking plate, Plane temperature difference of the substrate to be baked can be made uniform.

In the substrate baking method of the fourth invention, the baked substrate after the heating is further placed on the cooling plate and the cooling gas is discharged onto the baked substrate to uniformly cool the baked substrate.

[Example]

Hereinafter, the present invention will be described in detail with reference to exemplary embodiments with reference to the accompanying drawings.

FIG. 1 is a plan view showing the overall structure of a case where the baking apparatus according to the present invention is carried out for baking a photomask substrate. FIG. The baking apparatus comprises a baking chamber portion 11, a cooling portion 12, a transport mechanism portion 13, a substrate carrier 14, an operation panel 15, and the like. In such a configuration, by inputting an operation command from the operation panel 15, a plurality of photomask substrates 16 previously stored in the substrate carrier 14 are taken out one by one by the transport mechanism 13, The substrate 12 or the baking chamber portion 11 is cooled and baked. Then, the photomask substrate 16 after the completion of the entire baking process is transported to the substrate carrier 14 again by the transport mechanism 13 and stored.

Here, in this baking apparatus, the photomask substrate 16 is taken out, cooled, baked, and cooled sequentially from the substrate carrier 14 in accordance with a procedure programmed in advance by an operation command input from the operation panel 15, The process from the completion of the series of baking processes to the retention in the substrate carrier 14 is automatically performed.

FIG. 2 is a cross-sectional view showing the detailed structure of the baking chamber portion 11 for performing heat treatment of the substrate in the baking apparatus shown in FIG. 1. In the figure, reference numeral 21 denotes a lower heating plate. A rectangular photomask substrate 16 coated with photoresist is placed on the upper portion of the lower heating plate 21 through a proximity gap. Reference numeral 22 in the figure is for inserting a substrate transfer chuck (not shown) of the transfer mechanism unit 13. [

The lower heating plate 21 has a structure in which a heater 42 as a heating means is attached to the heating plate 41 as shown in the sectional view of FIG. 3, and a thermocouple The heater 42 is controlled in accordance with the output of the temperature controller 44 receiving the output of the thermocouple 43.

A crack ring 23 is fixed on the lower heating plate 21 so as to surround the periphery of the photomask substrate 16. The thickness of the crack ring 23 is substantially the same as that of the photomask substrate 16, and a tapered portion 24 having a tapered portion at a predetermined angle is formed in the periphery thereof. In addition, A storage portion 25 having a size slightly larger than that of the photomask substrate 16 is formed in order to accommodate the photomask substrate 16 as shown in Fig.

Furthermore, an upper heating plate 26 is provided above the lower heating plate 21. [ Like the lower heating plate 21, the upper heating plate 26 is provided with a heating plate, and a thermocouple and a temperature controller are provided to enable the temperature control while making the heater a heat source. In this upper heating plate 26, the heating amount with respect to the photomask substrate 16 located on the lower heating plate 21 is the smallest at the central portion, and the thickness at the central portion is set to be the largest at the central portion And the thickness gradually increases toward the peripheral portion from the central portion.

A chamber 27 is provided on the upper heating plate 26. In the baking process, the entire baking chamber portion 11 is covered by the chamber 27 so as to be shielded from the outside air, have.

Further, a gas injection hole 28 is formed at a position corresponding to the tapered portion 24 of the lower heating plate 21 in the peripheral portion of the upper heating plate 26. As shown in FIG. 5, the gas injection holes 28 are formed so as to extend substantially all around the upper heating plate 26. An inert gas such as a nitrogen gas is injected from the gas injection hole 28 by a gas supply means 29 shown in FIG. 2 at a predetermined flow rate. By this nitrogen gas flow, the upper heating plate 26 ) And the lower heating plate 21 is formed with a wall made of nitrogen gas. At this time, this nitrogen gas flow impinges on the tapered portion 24 formed on the lower heating plate 21 and diffuses to the side opposite to the side on which the photomask substrate 16 is housed, that is, to the outside, and a part of the nitrogen gas flow And enters the side where the photomask substrate 16 is housed. The temperature of this nitrogen gas flow is set at a temperature which does not impair the uniformity of the substrate temperature, or even higher. The uniformity of the temperature inside the substrate surface is improved by the change of the temperature and the flow rate of the nitrogen gas flow.

2 and 5, an opening 30 is provided at the center of the upper heating plate 26, and further, at a position corresponding to the opening 30 of the chamber 27, (31) are provided. From the opening 31, exhausting is performed at a predetermined flow rate by the exhausting means 32 shown in FIG.

In general, the photolithography process using the chemically amplified resist is performed in the order shown in the process of FIG. 6 (a). That is, after the resist is coated on the substrate having the chromium film formed on its surface, the substrate is cooled to room temperature. Next, the pattern is pre-baked, further cooled to room temperature, and then the pattern is drawn (EB drawing) by the electron beam drawing apparatus. Thereafter, the wafer is further cooled to room temperature, and after the electron beam lithography, the wafer is subjected to PEB, further cooled to room temperature, and then resist development is carried out, and the chromium film is selectively etched and resist stripped.

On the other hand, photolithography techniques using a non-chemically amplified resist are generally performed in the order shown in FIG. 6 (b). That is, the processes up to EB imaging are the same as those in the case of the chemically amplified resist, but after the EB imaging, the shape processing is performed. Thereafter, cooling (room temperature), post-baking and cooling (room temperature) The chromium film is selectively etched and the resist is peeled off.

The baking apparatus of the present embodiment is characterized in that it comprises a first baking step consisting of cooling (room temperature), pre-baking and cooling (room temperature) in the process of the photolithography technique and a first baking step consisting of cooling (room temperature) And a second baking step of cooling (room temperature). Next, a baking step in the case of using such a chemically amplified resist will be described. It is assumed that a 6-inch mask (a quartz substrate of 152.4 x 152.4 x 6.4 mm) is used as the photomask substrate and the flow rate of the nitrogen gas supplied from the gas injection hole 28 of the upper heating plate 26 is 0.5 to 5 It is noted that the flow rate of the exhaust gas from the openings 31 of the chamber 27 can be set in the range of 0.3 to 3 liters / minute. Further, it is assumed that the cooling section 12 is provided with a cooling plate set and maintained at room temperature in advance, for example, at 23 占 폚.

First, as a pre-step of the first baking step, a chemically amplified resist is dropped onto the photomask substrate 16 by a resist coating apparatus, and a resist layer of a predetermined film thickness is formed by spin- . Next, a plurality of substrates 16 are set on the substrate carrier 14, and an operation command is input from the operation panel 15. [ Thus, the substrate 16 is first conveyed to the cooling section 12, and is forcibly cooled for a predetermined time on a cooling plate set and maintained at a room temperature of 23 ° C. Next, the chamber 27 is opened in a state in which the flow rate of the sucking and discharging machine in the chamber 27 is 0.5 liters / minute, the set temperature of the lower heating plate 21 is set at 100 占 폚 and the set temperature of the upper heating plate 26 is set at 90 占 폚, The substrate 16 is placed on the lower heating plate 21 in the pre-bake process. Further, the temperature of the upper and lower heating plates can all be adjusted in the range of 60 to 200 ° C. At the time of prebaking, a crack ring 23 is provided around the substrate 16 on the lower heating plate 21. Heat is also applied from the side surface of the substrate 16 by the crack ring 23 , The temperature error between the central portion and the peripheral portion of the substrate 16 can be made very small.

Since the upper heating plate 26 capable of adjusting the temperature is provided on the upper portion of the substrate 16, the temperature distribution can be made uniform by heating the entire substrate by applying heat to the substrate 16 from above. In addition, the shape of the upper heating plate 26 is the thinnest at the central portion and gradually thicker from the central portion toward the peripheral portion so that the heating amount with respect to the substrate 16 is the smallest at the central portion and gradually increases from the central portion toward the peripheral portion It is possible to heat the peripheral portion having the lowest temperature by the heating by the lower heating plate 21 to a larger heating amount than the central portion, and as a result, the in-plane temperature difference of the substrate 16 can be made smaller have.

This prebaking step has an effect of improving the sensitivity by evaporating a part of the solvent in the resist coated on the substrate, but this baking has a great influence on the in-plane uniformity of the finished dimension of the resist. Therefore, by improving the in-plane temperature uniformity of the substrate, the in-plane uniformity of the finished dimension can be improved.

After the pre-baking is performed for 10 minutes, for example, the photomask substrate 16 is immediately transferred to the cooling section 12, where it is forcibly cooled for a predetermined time on a cooling plate set and maintained at a room temperature of 23 ° C.

The cooling unit 12 used for cooling the photomask substrate 16 is configured as shown in the front view of Fig. 8, for example. The substrate 16 is positioned on the line of the four fins 52a to 52d (52a, 52b only) of the cooling plate 51 by the transport mechanism 13. On the other hand, a buffer plate 54 and a rectifying plate 55 are fixed to the tip of the nozzle 53.

The buffer plate 54 is fixed to the nozzle 53 by a structure of a circulating material (flowable), for example, a screw 56 partially cut off. In addition, the four pins 52a to 52d are fixed to the air cylinder 57.

In the cooling section 12 having such a configuration, after the substrate 16 is placed on the four pins 52a to 52d, the air cylinder 57 is operated to lower the pins 52a to 52d, The nozzles 53 to which the buffer plate 54 and the flow regulating plate 55 are fixed by a structure not shown are brought into contact with the substrate 16 until the gap between the substrate 16 and the substrate 16 is about 0.1 mm, As shown in Fig.

A clean nitrogen gas is introduced from the injection hole 58 of the nozzle 53, and this nitrogen gas contacts the buffer plate 54 and diffuses to the outer periphery. Further, the flow regulating plate 55 and the substrate 16 are guided to form the same flow, and the substrate 16 is cooled. By making the size of the rectifying plate 55 larger than that of the substrate 16, the flow of the nitrogen gas on the upper surface of the substrate 16 can be made uniform, so that the cooling effect becomes uniform.

If the distance between the rectifying plate 55 and the substrate 16 is 20 mm or more, turbulence of nitrogen gas is generated and the cooling does not flow on the same outer circumference. Therefore, the interval is 20 mm or less .

Further, when the flow rate of the nitrogen gas is small, the cooling progresses from the outer periphery of the substrate 16, so that the temperature difference between the central portion and the substrate becomes large, and a large difference in resist sensitivity within the substrate surface is likely to occur. On the other hand, if the flow rate is too large, the cooling of the central portion becomes faster, and in this case, a large difference in resist sensitivity within the substrate surface is likely to occur. Actually, it has been found that when the flow rate is set in the range of 5 to 30 liters / minute, it can be uniformly cooled in the range of 2 to 5 占 폚.

Next, a second baking step consisting of cooling (room temperature), PEB and cooling (room temperature) in FIG. 6 (a) will be described. The substrate 16 on which the EB drawing is completed is forcibly cooled for a predetermined period of time on a cooling plate which is first conveyed to the cooling unit 12 and held at a room temperature set at 23 占 폚 as in the case of the first baking process. Next, the flow rate of the intake and exhaust gas in the chamber 27 is set to 0.5 liter / min, the set temperature of the lower heating plate 21 is set to 109 deg. C, and the set temperature of the upper heating plate 26 is set to 113 deg. The substrate 16 is placed on the lower heating plate 21 in the chamber 10 and the baking is started. Since the heat is also applied from the side surface of the substrate 16 by the crack ring 23 even in the PEB baking, the temperature error between the central portion and the peripheral portion of the substrate 16 can be made very small. In addition, since the entire substrate is heated by heating the substrate 16 from above, the temperature distribution can be made uniform. Further, the shape of the upper heating plate 26 is the least amount of heating with respect to the substrate 16, Since the thickness of the central portion is the thinnest and the thickness gradually increases toward the peripheral portion from the central portion so that the temperature is gradually lowered by the heating by the lower heating plate 21 The peripheral portion can be heated to a larger heating amount than the central portion. Accordingly, the in-plane temperature difference of the substrate 16 can be further reduced. When the temperature of the substrate 16 was measured at the time of PEB, a value of 3.0 占 폚 was maintained as an in-plane temperature error at the transient (60 占 폚) at the time of baking temperature rise. This value is considerably lower than that at 29 DEG C in the case of using a conventional apparatus.

FIG. 7 is a characteristic diagram showing the result of comparing the in-plane average temperature and the in-plane temperature error state of the substrate at the time of the temperature rise of the PEB process with that of the conventional device. As shown in the drawing, the in-plane temperature error in the transient state after 60 seconds from the start of baking is significantly reduced to 4.0 占 폚 in the case of this embodiment, compared with the conventional 25 占 폚. In the case of a ballast having passed 400 seconds from the start of baking, 0.2 deg. C could be realized in the present embodiment, while the conventional one was 8 deg.

As described above, in the embodiment, the in-plane temperature uniformity of the substrate in the baking step can be remarkably improved as compared with the conventional method.

This PEB is an important process for determining the error in the resist dimension in the chemically amplified resist, and is easily affected by the in-plane temperature error in the heating plate of the baking apparatus and the environment around the apparatus.

After the PEB is performed, for example, for 8 minutes, the substrate 16 is immediately conveyed to the cooling section 12, where it is forcibly cooled for a predetermined time on a cooling plate set and maintained at a room temperature of 23 deg. When the in-plane temperature difference of the substrate 16 was measured during this cooling, a value of 4.5 캜 was obtained. This value is considerably lower than 12 占 폚 in the case of using a conventional apparatus.

Next, the post-baking step in FIG. 6 (b) in the case of using a non-chemically amplified resist will be described. After the resist development, the substrate is forcibly cooled for a predetermined time on a cooling plate which is transported to the cooling section 12 and is set and maintained at a room temperature of 23 캜. Next, the chamber 27 is opened in a state in which the flow rate of the sucking and discharging machine in the chamber 27 is 0.5 liter / min, the set temperature of the lower heating plate 21 is 90 占 폚 and the set temperature of the upper heating plate 26 is 90 占 폚, The substrate is placed on the lower heating plate 21 in the substrate 10, and baking is performed, for example, for 10 minutes. This post-baking step serves to evaporate the developer by heating the resist pattern expanded by the developer, thereby shrinking the pattern. In this step, the uniformity of the finished resist pattern in the substrate can be improved. Thereafter, the substrate is immediately conveyed to the cooling section 12, where it is forcibly cooled for a predetermined time on a cooling plate set and maintained at a room temperature of 23 캜.

Next, various modifications of the substrate baking apparatus of the present invention will be described. In the above embodiment, the upper heating plate 26 is provided with a plurality of heating plates 26 as shown in FIG. 2, so that the amount of heating with respect to the substrate 16 positioned on the lower heating plate 21 is the smallest at the central portion and gradually increases from the central portion toward the peripheral portion. The case where the thickness at the central portion is the thinnest and the thickness gradually increases from the central portion toward the peripheral portion has been described. However, the shape of the upper heating plate 26 can be any shape or structure as long as it has the same function. For example, the upper heating plate 26 shown in Fig. 9 (a) has the thinnest thickness at the central portion and the thickness gradually increasing gradually from the central portion to the peripheral portion. The upper heating plate 26 shown in Fig. 9 (b) has the same thickness, but has a mountain shape in which the central portion is convex, and the distance between the lower heating plate 21 and the lower heating plate 21 In order to make it shorter. The upper heating plate 26 shown in FIG. 9 (c) is provided with a hollow 61 near the central portion. The upper heating plate 26 shown in FIG. 9 (d) has the least amount of heat applied to the substrate 16 at the central portion by the adjustment of the heater (not shown), and gradually increases from the central portion toward the peripheral portion.

In the above embodiment, a gas injection hole 28 is formed in the upper heating plate 26, nitrogen gas is injected from the gas injection hole, and the upper heating plate 26 and the lower heating plate 21 are filled with the nitrogen gas, The gas injection holes 28 are formed in the lower heating plate 21 as shown in FIG. 10, and the gas is injected from the gas injection holes 28 A nitrogen gas may be injected by the gas supply means 29 to form a wall.

In the above embodiment, the upper surface of the lower heating plate 21, that is, the position of the photomask substrate 16 is not particularly described. However, as shown in FIG. 11, the heating plate 41 The temperature of the central portion of the photomask substrate 16 can be lowered at the time of baking. In the case of a 6-inch mask (a quartz substrate having a size of 152.4 x 152.4 x 6.4 mm), the temperature at the central portion of the center of a diameter of 50 mm and the depth of 0.2 mm varies depending on the diameter and depth of the groove 62 Is increased by only 0.5 DEG C with respect to the average temperature in the substrate, so that it can be significantly reduced as compared with the case where the grooves 62 are not present.

In the above embodiment, the distance between the lower heating plate 21 and the upper heating plate 26 at the time of bake is not particularly described. However, as shown in FIG. 12, the distance between the upper heating plate 26 and the upper heating plate 26 The distance between the lower heating plate 21 and the upper heating plate 26 can be freely adjusted by vertically driving the arm 63 by rotating the ball screw 64 in accordance with the rotation of the motor 65 . With this configuration, the distance between the lower heating plate 21 and the upper heating plate 26 can be set to the optimum value depending on the thickness of the photomask substrate 16. [

In the above embodiments and modified examples, the case where the photomask substrate is used as the substrate to be baked has been described. However, it goes without saying that the present invention can also be applied to a semiconductor device such as a silicon substrate or a sapphire substrate, or a liquid crystal substrate .

In the above embodiment, the substrate is cooled to room temperature before and after baking, but this cooling step may be omitted depending on the case. Furthermore, in the above embodiment, the case where the pattern is formed on the resist using the electron beam drawing apparatus has been described. However, the present invention can be applied to all the baking processes of lithography techniques such as light and X-ray.

It should be noted that the drawings are not intended to limit the technical scope of the present invention to the embodiments shown in the drawings, in order to facilitate understanding of the present invention.

[Effects of the Invention]

As described above, according to the present invention, it is possible to provide a substrate baking apparatus and a substrate baking method capable of improving the uniformity of the in-plane temperature of the substrate in the baking step.

Claims (21)

A first heating plate 21 on which a photoresist is applied and on which a baked substrate 16 is placed or positioned with a predetermined gap therebetween; a second heating plate 26 ), A crack plate (23) provided on the first heating plate so as to surround the periphery of the baked substrate, and a container (27) for housing the first and second heating plates and the crack plate . The apparatus according to claim 1, wherein the first and second heating plates are provided with a heater (42) and a temperature detecting means (43), respectively, wherein the first and second heating plates (44). ≪ / RTI > The substrate baking apparatus according to claim 1, wherein a groove (62) is provided at a central portion of a position surface of the baking substrate of the first heating plate. The substrate baking apparatus according to claim 1, wherein the photoresist is a chemically amplified photoresist. The substrate baking apparatus according to claim 1, wherein the second heating plate is configured such that a heating amount with respect to the substrate to be baked gradually increases from a central portion toward a peripheral portion. The substrate baking apparatus according to claim 5, wherein the thickness of the second heating plate is gradually increased from the central portion toward the peripheral portion so that the amount of heating with respect to the substrate is sequentially increased from the central portion toward the peripheral portion. 6. The substrate according to claim 5, characterized in that the distance between the second heating plate and the first heating plate is gradually shortened from the central portion toward the peripheral portion so that the heating amount with respect to the substrate to be baked gradually increases from the central portion toward the peripheral portion Baking device. The substrate baking apparatus according to claim 5, wherein a cavity is provided in the vicinity of a central portion of the second heating plate so that a heating amount with respect to the baking substrate gradually increases from a central portion toward a peripheral portion. The substrate baking apparatus according to claim 1, wherein means for arbitrarily adjusting the interval between the first heating plate and the second heating plate is provided. 2. The apparatus according to claim 1, wherein a gas injection hole (28) is provided in a peripheral portion of the second heating plate, an opening (30) is provided in a central portion of the second heating plate, And an exhaust hole (31) is provided in the vicinity of the substrate. The exhaust gas purification apparatus according to claim 10, further comprising: gas injection means (29) for injecting a predetermined gas at a predetermined flow rate from a gas injection hole (28) provided in the second heating plate, Further comprising gas discharging means (32) for discharging the gas discharged from the opening of the central portion at a predetermined flow rate. The heat exchanger according to claim 1, wherein a first heating plate (21) and a gas injection hole (28) penetrating the crack plate (23) are provided in a peripheral portion of the first heating plate And an exhaust hole (31) is provided in the vicinity of a position corresponding to the opening of the container. 13. The exhaust gas purification apparatus according to claim 12, further comprising a gas injection means (29) for injecting a predetermined gas at a predetermined flow rate from a gas injection hole (28) provided in the first heating plate, And gas discharge means (32) for discharging the gas discharged from the opening of the chamber (32) at a predetermined flow rate. A first heating plate (21) on which a photoresist is applied and on which a baked substrate (16) is placed directly or with a predetermined gap therebetween; a second heating plate (21) disposed above the photoresist application surface of the baked substrate, A second heating plate (26) provided close to a peripheral portion of the baking substrate, a crack plate (23) provided on the first heating plate so as to surround the periphery of the baking substrate, a first heating plate And a cooling plate (51) for cooling the above-mentioned substrate to be baked. Baking a substrate to which a photoresist is applied on a surface thereof, placing the substrate to be baked on a cooling plate for a predetermined time to uniformize the temperature of the substrate to be baked, thereafter placing the baked substrate on the first heating plate, Wherein the heating is carried out in a state in which the periphery of the substrate to be baked is surrounded by a crack plate and a second heating plate is disposed above the photoresist application surface of the substrate to be baked. 16. The method of claim 15, wherein the photoresist is a chemically amplified photoresist. 16. The substrate baking apparatus according to claim 15, wherein the heating is performed in such a state that the heating amount of the second heating plate with respect to the baked substrate is gradually increased from the central portion to the peripheral portion at the time of heating the substrate. 16. The method according to claim 15, wherein a gas injection hole is provided in a peripheral portion of the second heating plate, and a predetermined gas is supplied from the gas injection hole to the first heating plate at a predetermined flow rate, And the substrate is heated while the substrate is surrounded by the wall by the gas flow and the first and second heating plates. 19. The substrate baking method according to claim 18, wherein an exhaust hole (31) is provided in the container, and exhausting is performed at a predetermined flow rate from the exhaust hole when heating the substrate to be baked. In baking a baked substrate having a photoresist applied on its surface, the baked substrate is cooled to homogenize the temperature, the baked substrate is then placed on the first heated plate, and the periphery of the baked substrate is set as a crack plate The second heating plate is placed above the coated surface of the photoresist of the substrate to be baked, heated in the vessel, the baked substrate after the heating is placed on a cooling plate, the cooling gas is discharged from the baking substrate And the substrate to be baked is cooled. 21. The method of claim 20, wherein the scraped photoresist is a chemically amplified photoresist.